Detect host OS based on USB fingerprint (#18463)

Co-authored-by: Drashna Jaelre <drashna@live.com>
Co-authored-by: Nick Brassel <nick@tzarc.org>

1 files changed, 129 insertions, 0 deletions

diff --git a/quantum/os_detection.c b/quantum/os_detection.c
new file mode 100644
index 0000000000..b1511afb14
--- /dev/null
+++ b/quantum/os_detection.c
@@ -0,0 +1,129 @@
+/* Copyright 2022 Ruslan Sayfutdinov (@KapJI)
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include "os_detection.h"
+
+#include <string.h>
+
+#ifdef OS_DETECTION_DEBUG_ENABLE
+#    include "eeconfig.h"
+#    include "eeprom.h"
+#    include "print.h"
+
+#    define STORED_USB_SETUPS 50
+#    define EEPROM_USER_OFFSET (uint8_t*)EECONFIG_SIZE
+
+uint16_t usb_setups[STORED_USB_SETUPS];
+#endif
+
+#ifdef OS_DETECTION_ENABLE
+struct setups_data_t {
+    uint8_t      count;
+    uint8_t      cnt_02;
+    uint8_t      cnt_04;
+    uint8_t      cnt_ff;
+    uint16_t     last_wlength;
+    os_variant_t detected_os;
+};
+
+struct setups_data_t setups_data = {
+    .count       = 0,
+    .cnt_02      = 0,
+    .cnt_04      = 0,
+    .cnt_ff      = 0,
+    .detected_os = OS_UNSURE,
+};
+
+// Some collected sequences of wLength can be found in tests.
+void make_guess(void) {
+    if (setups_data.count < 3) {
+        return;
+    }
+    if (setups_data.cnt_ff >= 2 && setups_data.cnt_04 >= 1) {
+        setups_data.detected_os = OS_WINDOWS;
+        return;
+    }
+    if (setups_data.count == setups_data.cnt_ff) {
+        // Linux has 3 packets with 0xFF.
+        setups_data.detected_os = OS_LINUX;
+        return;
+    }
+    if (setups_data.count == 5 && setups_data.last_wlength == 0xFF && setups_data.cnt_ff == 1 && setups_data.cnt_02 == 2) {
+        setups_data.detected_os = OS_MACOS;
+        return;
+    }
+    if (setups_data.count == 4 && setups_data.cnt_ff == 0 && setups_data.cnt_02 == 2) {
+        // iOS and iPadOS don't have the last 0xFF packet.
+        setups_data.detected_os = OS_IOS;
+        return;
+    }
+    if (setups_data.cnt_ff == 0 && setups_data.cnt_02 == 3 && setups_data.cnt_04 == 1) {
+        // This is actually PS5.
+        setups_data.detected_os = OS_LINUX;
+        return;
+    }
+    if (setups_data.cnt_ff >= 1 && setups_data.cnt_02 == 0 && setups_data.cnt_04 == 0) {
+        // This is actually Quest 2 or Nintendo Switch.
+        setups_data.detected_os = OS_LINUX;
+        return;
+    }
+}
+
+void process_wlength(const uint16_t w_length) {
+#    ifdef OS_DETECTION_DEBUG_ENABLE
+    usb_setups[setups_data.count] = w_length;
+#    endif
+    setups_data.count++;
+    setups_data.last_wlength = w_length;
+    if (w_length == 0x2) {
+        setups_data.cnt_02++;
+    } else if (w_length == 0x4) {
+        setups_data.cnt_04++;
+    } else if (w_length == 0xFF) {
+        setups_data.cnt_ff++;
+    }
+    make_guess();
+}
+
+os_variant_t detected_host_os(void) {
+    return setups_data.detected_os;
+}
+
+void erase_wlength_data(void) {
+    memset(&setups_data, 0, sizeof(setups_data));
+}
+#endif // OS_DETECTION_ENABLE
+
+#ifdef OS_DETECTION_DEBUG_ENABLE
+void print_stored_setups(void) {
+#    ifdef CONSOLE_ENABLE
+    uint8_t cnt = eeprom_read_byte(EEPROM_USER_OFFSET);
+    for (uint16_t i = 0; i < cnt; ++i) {
+        uint16_t* addr = (uint16_t*)EEPROM_USER_OFFSET + i * sizeof(uint16_t) + sizeof(uint8_t);
+        xprintf("i: %d, wLength: 0x%02X\n", i, eeprom_read_word(addr));
+    }
+#    endif
+}
+
+void store_setups_in_eeprom(void) {
+    eeprom_update_byte(EEPROM_USER_OFFSET, setups_data.count);
+    for (uint16_t i = 0; i < setups_data.count; ++i) {
+        uint16_t* addr = (uint16_t*)EEPROM_USER_OFFSET + i * sizeof(uint16_t) + sizeof(uint8_t);
+        eeprom_update_word(addr, usb_setups[i]);
+    }
+}
+
+#endif // OS_DETECTION_DEBUG_ENABLE